Paper board locks



Feb. 4, 1958 H. s. MEYERS PAPER BOARD LOCKS Filed Feb. 9. 1955INVENTORJM Harv/a 5f Meyers .AT'I ORNEY United States Patent" PAPERBOARD LOCKS Harold S. Meyers, Minneapolis, Minn., assignor to WaldorfPaper Products Company, Ramsey County, Minn.,

a corporation of Minnesota Application February 9, 1955, Serial No.487,155

6 Claims. (Cl. 24-73) This invention relates to an. improvement in paperboard locks and deals particularly with a means of locking one piece ofpaper board into another.

In the formation of displays and particularly those made of corrugatedpaper board, some difliculty has been experienced in locking one pieceof paper board extending through a slot in the other. In calling for twopieces of paper board, itshould be understood that both pieces may beintegrally connected together. The present invention deals with a simpleand effective means of locking the two parts together.

A feature of the present invention lies in the simplicity with which thelocking engagement may be completed. Under normal circumstances a slotis formed in one piece and a tab is designed to extend through thisslot. The tab is of proper size to fit through the slot withoutinterference. When once inserted, the lock is formed by bending portionsof the inserted tab out of alignment with the slot, thus preventing thewithdrawal of the tab through the slot. I

A feature of the present invention lies in the provision of a tabdesigned to extend through a slot and in providing a T-shaped slit inthe tab with the cross member of the T extemdingsubstantially flush withthe inner surface of the sheet containing the slot when the tab is fullyinserted. The main stem of the T-shaped slot extends towards the freeend of the tab.v As a result, after the tab has .been inserted, thetriangular areas between. the non-connected ends of the T-shaped slitcan be bent out of plane of the tab to lock the tab from removal.

A further feature of the present invention lies in the fact that notonly can the tab be used to lock (folded portions of the same sheet inangular relation, but also the lock may be used to secure twothicknesses of paper board in surface contact. This is accomplished byproviding a locking member formed of a U-shaped strip of paper boardarranged so that the base of the U will lie in surface contact with oneof the sheets to be connected and the sides of the U-shaped member mayextend through slots to extend through the sheets at right anglesthereto. When the sides of the U are locked in place, the two sheets aresecurely fastened in surface contact.

These and other objects and novel features of my invention will be moreclearly and fully set forth in the following specification and claims.

In the drawings forming a part of the specification:

Figure 1 is a perspective view of a generally rectangular post formed ofcorrugated paper board showing a locking tab holding the post in propershape.

Figure 2 is a diagrammatic view of the blank from which the post isformed.

Figure 3 is an elevational view of the rear of the sheet with thelocking tab in locking position.

Figure 4 is a perspective view of a display showing. an easel connectedto a display panel.

Figure 5 is a diagrammatic view of the blank from 2 which the lockingmember illustrated in Figure 4 is formed.

Figure 6 is a sectional view through the display of Figure 4 showing themanner in which the locking member locks the easel to the display panel.

There are many uses for a lock which is designed to hold a tabprojecting through a panel at right angles thereto. The structuresillustrated in the drawings are merely fragmentary and for the purposeof illustration. However, many displays are formed with tubular postsalong opposite edges thereof, designed to stiffen the display and holdit in proper shape. Furthermore, there are many instances in which it isdesired to lock two panels in surface contact. The present structure isdesirable for such purposes in any case where the inserted ends of thetab or tabs are accessible after they have been inserted.

In the form of construction shown in Figures 1, 2. and 3, a displaypanel 10 is connected along one edge 11 to a side flange 12. The sideflange 12 is connected along a fold line 13 to a front flange 14. Thisfront flange 14 is connected along a fold line 15 to a side flange 16.This si'de flange 16 isin turn provided with a projecting tab 17designed to extend through a slot 19 in the panel 10. When the structurethus formed has been folded, a tu-. bular post is provided extendingalong an edge of the display panel. Various means have been used foranchoring a structure of this type inproper position. For example, aflange may be foldably connected to the flange of panel 16 and designedto fold flat against the surface of the panel 10. This anchoring flangemay be secured to the display panel by adhesive, stitching or othersuch.

. cross bar portion 21 which is designed to extend substantially. flushwith the inner surface-of the panel through right angular main's'te'mportion '22 which communicates with the slit 21 and extends rightangularly from the center thereof.

With the structure thus described, the tab 17 may be inserted throughthe slot 19 without difiiculty as this slot 19 is of proper dimensionsto accommodate the tab. After the tab has been inserted, the portion ofthe tab adjoining the slits is pressed inwardly with the thumb orfingers. This action bends the triangular areas between the rightangular slit lines out of the plane of the remainder of the tab andengages over the inner surface of the panel 10 as is best indicated inFigure 1 of the drawings. As the stock is bent at these areas and as theedges of the triangular parts are flush with the inner surface or rearsurface of the panel 10, the triangular areas indicated at 23 and 24frictionally engage the panel and are held out of the plane of the tab.In actual practice the slit 21 may be slightly inwardly of the surfaceof the panel so that when the triangular areas are forced out of theplane of the tab, they bind in this position.

Figures 4, 5 and 6 disclose a modified form of construction embodyingthe same type of lock. For the purpose of example, the drawings show adisplay panel 25 which is to be secured to an easel such as 26. Theeasel includes a center panel 27 designed to lie in surface contact withthe rear side of the display panel 25 and includes spaced wings 29secured to opposite side edges of the center panel 27 so as to supportthe display panel 25 in an upright position. The problem involved is tosecure the Patented Feb. 4, 1958 panels 25 and 27 in surface contactwithout the use of staples, adhesive or other such means.

In order to accomplish this result a lock 30 of the type bestillustrated in Figure is formed. This lock comprises a U-shaped memberincluding a central panel 31 and a pair of locking tabs 32 and 33connected to the center panel 31 along opposite fold lines 34 and 35.The tabs 32 may be folded at right angles to the center panel 31 toproject through the display panel 25 and through the panel 27.

A pair of parallel slots 36 and 37 are provided in the panel 25 and apair of aligned slots 39 and 40 are provided in the easel panel 27.These slots are of proper size to freely accommodate the tabs 32 and 33which project therethrough at right angles to the surface thereof.

Each of the tabs 32 and 33 is provided with a T-shaped slit 41 therein.This T-shaped slit 41 includes a slit 42 designed to extend parallel tothe fold lines 34 and 35 and spaced therefrom a distance approximatelyequal to, or slightly less than, the combined thickness of the panels 25and 27. The slits also include portions 43 which extend at right angleto the slits 42 and communicate with the center thereof. Thus the slitsform two sides of two triangular areas which may be bent out of plane ofthe remaining portions of the tabs 32 and 33.

In assembling the easel illustrated it is only necessary to place theeasel in surface contact with the rear side of the display panel so thatthe slots 36 and 37 of the display panel align with the slots 39 and 40of the easel. The tabs 32 and 33 are then inserted through the alignedslots. Pressure is then exerted with the thumbs or fingers against thetriangular areas defined by the T-shaped slots, bending these areas outof plane of the remainder of the tabs. These portions will frictionallyengage the rear surface of the panel 27 and prevent withdrawal of thetabs from the slots thus locking the two parts together.

As the locking member 30 is of small size it can usually be cut fromwaste portions of the blank from which the display is made and may besimultaneously printed if desired so that the visible portion of thelock will not detract from the appearance. For example, in one displayshowing a Santa Claus figure, the lock was attached centrally andprinted to indicate a belt buckle and thereby enhancing the appearanceof the display rather than detracting from it.

In accordance with the patent statutes, I have described the principlesof construction and operation of my paper board locks, and while I haveendeavored to set forth the best embodiment thereof, I desire to have itunderstood that obvious changes may be made within the scope of thefollowing claims without departing from the spirit of my invention.

I claim:

1. A lock for anchoring a tab extending at right angles to a panel, thestructure including a tab, and a panel having a slot therein throughwhich the tab may extend, said tab having a generally T-shaped slitarranged with the cross bar portion of the slit extending along asurface of the panel, said slit defining two triangular portions whichmay be flexed out of the plane of the tab.

2. The construction described in claim 1 and including means forlimiting the insertion of the tab through the slot.

3. A lock for anchoring a tab extending through a panel and including apanel, flange means foldably connected thereto, a tab connected to themarginal edge of one of said flange means, said panel having a slotthrough which said tab may extend when said flange means are foldedangularly to the panel, said tab means having a T-shaped slit, the crossmember of the T-shaped slit extending substantially flush with thesurface of the panel through which the tab has been inserted.

4. The construction described in claim 3 and in which said flange meanslimits the insertion of said tab means through said slot.

5. A look for holding a pair of panels in surface contact, the structureincluding a pair of panels having spaced slots extending therethrough,the slots of the two panels being registerable, a locking element havinga panel portion designed to overlie one of said panels, said lockingelement also including tabs engageable through said slots, each of saidtabs having T-shaped slits with the cross bar portions of the slitsextending substantially flush with the surface of the other panelthrough which the tabs are inserted.

6. The construction described in claim 5 and in which said slots areparallel.

References Cited in the file of this patent UNITED STATES PATENTS

